N-Alkyl or alkoxy-N&#39;-substituted hydrocarbyl urea

ABSTRACT

Compounds of the formula   &lt;IMAGE&gt;   wherein R is aliphatic hydrocarbyl, alicyclic hydrocarbyl or aryl suitably substituted, if desired, or a heterocyclic group, R1 is hydrogen or alkyl, R2 is alkyl or alkoxy, R3 is   &lt;IMAGE&gt;  wherein a is 0 or 1, R4 is hydrogen or CW&#39;3, the W&#39; being hydrogen or halogen, Z is halogen and X is halogen, hydroxy, alkoxy, acetoxy, carbethoxyalkoxy, phenoxy, alkylthio, carbethoxyalkylthio, phenylthio, phosphono, dithiophosphonoxy, phosphoramido, isocyanato, isothiocyanato, alkyl- and dialkylthiocarbamoylthio, alkyl- and dialkylcarbamoyloxy, alkylsulfonyl, etc., have herbicidal activity.

RELATED APPLICATIONS

This application is a division of application Ser. No. 68,039, filedAug. 20, 1979, now U.S. Pat. No. 4,273,572, which is a division ofapplication Ser. No. 919,016, filed June 26, 1978, now U.S. Pat. No.4,200,450, which is a division of application Ser. No. 741,422, filedNov. 12, 1976, now U.S. Pat. No. 4,111,683, which is acontinuation-in-part of application Ser. No. 591,058, filed June 27,1975, and now abandoned, which, in turn, is a continuation ofapplication Ser. No. 385,521, filed Aug. 3, 1973, now abandoned, whichapplication is, in turn, a continuation-in-part of applications Ser.Nos. 124,422 and 124,423, both filed Mar. 16, 1971, both abandoned, thediscosures of all of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION 1. Field

The present invention is concerned with ureas having herbicidalactivity. Particularly, the present invention is concerned with 1-alkylor 1-alkoxy-1-(1-substituted aliphatic hydrocarbyl)-3-substitutedhydrocarbyl ureas and their use as herbicides.

2. Prior Art

U.S. Pat. No. 3,040,082 discloses beta-polyhaloalpha-hydrocarbylisocyanates and derivatives thereof, such as1-(1-hydroxy-2,2,2-trifluoroethyl)-3-phenyl urea and1-(1-hydroxy-2,2,2-trichloroethyl)-3-phenyl urea, and their use asherbicides. Hoover et al., J. Org. Chem. 28(7), 1825-30 (1963) disclosecompounds such as 1-(1-hydroxy-2,2,2-trifluoro-1-chloroethyl)-3-phenylurea. Chattaway et al, Proc. Roy. Soc. (London) A-134, pages 372-84(1931) and Chattaway et al., J. Chem. Soc. 1933, 30, disclose compoundsprepared by the condensation of chloral with tolyl and nitrophenylureas. Also, U.S. Pat. Nos. 2,846,399; 2,902,356; 3,418,334 and3,488,376 disclose ureas and their uses.

DESCRIPTION OF THE INVENTION

Compounds of the present invention may be represented by the formula##STR3## wherein R is an aliphatic hydrocarbyl group of 1 to 12 carbonatoms substituted with 0 to 4 halogen atoms of atomic number 17 to 35(chlorine or bromine), an alicyclic hydrocarbyl group of 3 to 8 carbonatoms substituted with 0 to 4 halogen atoms of atomic number 17 to 35,an aryl group of 6 to 12 carbon atoms substituted with 0 to 5 halogenatoms of atomic number 9 to 35 (fluorine, chlorine or bromine), nitro,alkyl of 1 to 4 carbon atoms, alkoxy of 1 to 4 carbon atoms, alkylthioof 1 to 4 carbon atoms, or 0 to 1 alkylsulfoxy of 1 to 4 carbon atoms,alkylsulfonyl of 1 to 4 carbon atoms, trifluoromethyl, phenoxy,phenylthio, phenylsulfoxy, phenylsulfonyl, the phenoxy, phenylthio,phenylsulfoxy or phenylsulfonyl being substituted on the aromaticnucleus with 0 to 5 halogens of atomic number 9 to 35 or alkyl of 1 to 4carbon atoms; or a heterocyclic group of 5 to 6 atoms containing 1 to 2heteroatoms of oxygen, sulfur or nitrogen and being attached to the ureanitrogen through a carbon atom; R¹ is hydrogen or alkyl of 1 to 4 carbonatoms, R² is alkyl of 1 to 4 carbon atoms or alkoxy of 1 to 4 carbonatoms and R³ is ##STR4## wherein a is 0 to 1 and R⁴ is hydrogen or CW'₃,W' representing hydrogen or halogen of atomic number 9 to 35, Z ishalogen of atomic number 9 to 35, and X is

(1) --U'R⁵ wherein U' is O or S, R⁵ is hydrogen, alkyl of 1 to 4 carbonatoms substituted with 0 to 4 halogen atoms of atomic number 9 to 35,phenyl substituted with 0 to 4 halogen atoms of atomic number 9 to 35,nitro, alkyl of 1 to 4 carbon atoms, or alkoxy of 1 to 4 carbon atoms,with the proviso that when R⁵ is hydrogen, U' is S;

(2) --P(O) (OR⁶)₂, wherein R⁶ is alkyl of 1 to 4 carbon atoms; ##STR5##wherein R⁷ is hydrogen or alkyl of 1 to 4 carbon atoms substituted with0 to 4 halogen atoms of atomic number 9 to 35, or an amino groupoptionally substituted with 1 to 2 alkyl groups individually of 1 to 4carbon atoms or 1 aryl group, and U' is as defined above;

(4) --N═C═U', wherein U' is as defined above; ##STR6## wherein U' and R⁶are as defined above; ##STR7## wherein R⁸ is alkyl of 1 to 4 carbonatoms substituted with 0 to 4 halogen atoms of atomic number 9 to 35 andU' is as defined above; ##STR8## wherein R⁶ is as defined above;##STR9## wherein U' and R⁶ are as defined above;

(9) fluorine, chlorine, bromine, iodine; or

(10) hydroxy.

Preferably R is alkyl of 1 to 12 carbon atoms, optionally substitutedwith halogen atoms, cycloalkyl of 3 to 8 carbon atoms, preferably 5 to 6carbon atoms optionally substituted with halogen atoms or phenyloptionally substituted with halogen, nitro, alkyl, alkoxy, alkylthio,alkylsulfoxy, alkylsulfonyl, trifluoromethyl, phenoxy, phenylthio,phenylsulfoxy, phenylsulfonyl, the phenoxy, phenylthio, phenylsulfoxy,or phenylsulfonyl being optionally substituted on the aromatic nucleuswith halogen or alkyl. The substituents, alkylsulfoxy, alkylsulfonyl,phenoxy, phenylthio, phenylsulfoxy or phenylsulfonyl optionallysubstituted on the aromatic nucleus, as the case may be, are preferablyattached to the phenyl group in the p-position. The tri-fluoromethylgroup is preferably attached to the phenyl group in the o-position. Itis particularly preferred that the total number of substituents on thearyl group (or phenyl group) not exceed 2 and that when one of thesubstituents is alkylsulfoxy, alkylsulfonyl, trifluoromethyl, phenoxy,phenylthio, phenylsulfoxy or phenylsulfonyl that the other substitutent,if any, be halogen, nitro or alkyl.

The preferred compounds of the present invention may thus be representedby the formula ##STR10## wherein R¹, R² and R³ are as described aboveand Y is halogen of atomic number 9 to 35, nitro, alkyl of 1 to 4 carbonatoms, alkoxy of 1 to 4 carbon atoms, alkylthio of 1 to 4 carbon atoms,alkylsulfoxy of 1 to 4 carbon atoms, alkylsulfonyl of 1 to 4 carbonatoms, trifluoromethyl, phenoxy, phenylthio, phenylsulfoxy,phenylsulfonyl, the phenoxy, phenylthio, phenylsulfoxy or phenylsulfonylbeing substituted on the aromatic nucleus with 0 to 5 halogen atoms ofatomic number 9 to 35 or alkyl of 1 to 4 carbon atoms and n is 0 to 5when Y is halogen, nitro, alkyl, alkoxy or alkylthio, and 0 to 1 when Yis alkylsulfoxy, alkylsulfonyl, trifluoromethyl, phenoxy, phenylthio,phenylsulfoxy or phenylsulfonyl. Preferably Y in the above formula (II)is halogen of atomic number 9 to 35 (fluorine, chlorine or bromine),more preferably fluorine or chlorine, alkyl of 1 to 2 carbon atoms,alkoxy of 1 to 2 carbon atoms or trifluoromethyl, and n is preferably 0or an interger from 1 to 2.

In the above formula, R¹ is preferably hydrogen and R² is preferablyalkyl of 1 to 4 carbon atoms, more preferably methyl.

Preferably R³ in the above formula is ##STR11## wherein A is 0 or 1 andR⁴, X and Z are as defined above. More preferably R⁴ is hydrogen,trichloromethyl, trifluoromethyl or methyl and Z is fluorine, chlorineor bromine. Still more preferably, a is 0 and Z is fluorine, chlorine orbromine.

Thus the particularly preferred compounds of the present invention maybe represented by the formula ##STR12## wherein R¹, R², Y, n, X and Zare as defined above. In particular, n will be from 1 to 2 and Y will befluorine, chlorine or bromine, particularly fluorine in the o-position,chlorine in the o-, m- or p-position and the bromine in the p-position.

Preferably R⁵ is hydrogen, methyl, ethyl or phenyl, R⁶ is methyl orethyl, R⁷ is hydrogen, methyl or ethyl or an amino group substitutedwith at least one alkyl group of 1 to 2 carbon atoms (methyl or ethyl)and R⁸ is methyl or ethyl.

More particularly, it is preferred that when X is either ##STR13## thatboth U's in the radical represent the same atom, that is, either oxygenor sulfur.

The most preferred compounds of formula (III) are those wherein X ishalogen, especially fluorine, chlorine, or alkylthio, especiallymethylthio. Compounds with X equal to fluorine are preferred in partbecause of their stability.

Representative groups which R may represent include:

methyl,

ethyl,

n-propyl,

isopropyl,

n-butyl,

isobutyl,

sec.butyl,

decyl,

dodecyl,

chloromethyl,

chloroethyl,

cyclopropyl,

cyclobutyl,

cyclopentyl,

cyclohexyl,

phenyl,

naphthyl,

2-fluorophenyl,

2-chlorophenyl,

2-chloro-4-bromophenyl,

3-methylphenyl,

4-methoxyphenyl,

2-nitrophenyl,

4-methylthiophenyl

4-methylsulfoxyphenyl,

4-methylsulfonylphenyl,

2-trifluoromethylphenyl,

4-phenoxyphenyl,

4-phenylthiophenyl,

4-phenylsulfoxyphenyl,

4-phenylsulfonylphenyl,

4-(2-chlorophenoxy)phenyl, 3-methyl-4-phenylthiophenyl,

thiazolyl,

pyridyl,

pyrimidyl,

oxazolyl,

isothiazolyl,

furyl, and

thienyl.

Representative groups which R¹ may represent include: hydrogen, methyl,ethyl, n-propyl, isopropyl, etc.

Representative groups which R² may represent include:

methyl,

ethyl,

n-propyl,

isopropyl,

n-butyl,

isobutyl,

methoxy,

ethoxy, etc.

Representative groups which R³ may represent include:

1-methoxy-2,2,2-trifluoromethyl,

1-methylthio-2,2-dibromo-2-chloroethyl,

1-acetoxy-2,2-dichloro-3,3-bromopropyl,

1-phenoxy-2-bromo-2-chlorovinyl,

1-ethoxy-2,3-dibromo-3,3-difluoropropyl,

1-methoxy-2,3,3-trichloro-2-propenyl, etc.

Representative groups which R⁴ may represent include:

trifluoromethyl,

difluoromethyl,

dichloromethyl,

fluorochloromethyl, etc.

Representative groups which X may represent include:

fluorine,

chlorine,

bromine,

iodine,

hydroxy,

methoxy,

ethoxy,

chloromethoxy,

methylthio,

phenoxy,

2-chlorophenoxy,

3-nitrophenoxy,

4-methoxyphenylthio,

dimethylphosphono,

diethylphosphono,

methylethylphosphono,

acetoxy,

propionoyloxy,

chloracetoxy,

methylcarbamolyoxy,

ethylcarbamoyloxy,

dimethylcarbamoyloxy,

methyl thiocarbamoylthio,

isocyanato,

isothiocyanato,

O,O-dimethylphosphoramido,

O,O-dimethylthiophosphoramido,

carbmethoxymethylthio,

methylsulfonyl,

ethylsulfonyl, etc.

Representative compounds of the present invention include:

1-methyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-phenyl urea,

1-ethyl-1-(1-hydroxy-2,2,2-trifluoroethyl-3-(2-chlorophenyl)urea,

1-methyl-1-(1-hydroxy-2,2,2-tribromoethyl)-3-(2-fluorophenyl)urea,

1-methoxy-1-(1-hydroxy-2,2-dichloro-2-fluoroethyl)-3-(2-nitrophenyl)urea,

1-methyl-1-(1-hydroxy-2,2-dichloroethyl)-3-(4-methylphenyl)urea,

1-butyl-1-(1-hydroxy-2,2,2-trifluoroethyl)-3-(4-methoxyphenyl)urea,

1-ethoxy-1-(1-hydroxy-2,2,2-tribromoethyl)-3-methyl-3-(3,4-dichlorophenyl)urea,

1-methyl-1-(1-hydroxy-2,2,3,3,3-pentachloropropyl)-3-phenyl urea,

1-ethyl-1-(1-hydroxy-2,2-dichloro-3,3-difluoropropyl)-3-pentachlorophenylurea,

1-methyl-1-(1-hydroxy-2,2-dichloropropyl)-3-(2-chloro-4-methoxyphenyl)urea,

1-methyl-1-(1-hydroxy-2,3,3-trichloro-1-propenyl)-3-(2-nitrophenyl)urea,

1-methyl-1-(1-hydroxy-2-chloro-1-propenyl)-3-(2,4,6-trichlorophenyl)urea,

1-methyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-(4-phenoxyphenyl)urea,

1-methyl-1-(1-hydroxy-2,3,3,3-tetrachloro-1-propenyl)-3-(2-fluorophenyl)urea,

1-methyl-1-(1-hydroxy-2,2,2-tribromoethyl)-3-(4-[2'-chlorophenoxy]phenyl)urea,

1-methyl-1-(1-hydroxy-2,2,2-trifluoroethyl)-3-(3-trifluoromethylphenyl)urea

1-methyl-1-(1-hydroxy-2-chloro-2-propenyl)-3-(3-chlorophenyl)urea,

1-methyl-1-(1-hydroxy-2,2,3,3-tetrachloropropyl)-3-(2-trifluoromethylphenyl)urea,

1-methyl-1-(1-hydroxy-2,2-dichlorovinyl)-3-(3-trifluoromethylphenyl)urea,

1-methyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-methyl urea,

1-methyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-ethyl urea,

1-methyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-dodecyl urea,

1-methyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-cyclopentyl urea,

1-methyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-cyclohexyl urea,

1-methyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-(2-thiazolyl)urea,

1-methyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-(4-thiazolyl)urea,

1-ethyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-(2-pyridyl)urea,

1-ethyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-(3-pyridyl)urea,

1-methyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-(2-pyrimidyl)urea,

1-methyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-(5-pyrimidyl)urea,

1-methyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-(2-furyl)urea,

1-methyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-(4-methylthiophenyl)urea,

1-methyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-(4-methylsulfoxyphenyl)urea,

1-methyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-(4-methylsulfonylphenyl)urea,

1-methyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-(4-phenoxyphenyl)urea,

1-ethoxy-1-(1-hydroxy-2,2,2-tribromoethyl)-3-(4-phenoxyphenyl)urea,

1-methyl-1-(1-hydroxy-2,2,3,3,3-pentachloropropyl)-3-(2-chloro-4-[2'-chlorophenoxy]phenyl)urea,

1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-phenyl urea,

1-ethyl-1-(1,2,2,2-tetrachloroethyl)-3-(4-chlorophenyl)urea,

1-methyl-1-(1-chloro-2,2,2-trifluoroethyl)-3-(2,4-difluorophenyl)urea,

1-methyl-1-(1-bromo-2,2,2-trichloroethyl)-3-(2,3,4-trinitrophenyl)urea,

1-methyl-1-(1-iodo-2,2,2-trichloroethyl)-3-(2-fluorophenyl)urea,

1-methoxy-1-(1-chloro-2,2,2-tribromoethyl)-3-(2-trifluoromethylphenyl)urea,

1-ethoxy-1-(1,2,2,3-tetrachloropropyl)-3-(2-fluorophenyl)urea,

1-methyl-1-(1,2,2-trichloro-3,3,3-trifluoropropyl)-3-(3,5-dichlorophenyl)urea,

1-methyl-1-(1,2,3-trichloro-1-propenyl)-3-(2-chlorophenyl)urea,

1-methyl-1-(1,2,2-trichloropropyl)-3-(3-methyl-4-methoxyphenyl)urea,

1-methyl-1-(1,2,3,3-tetrachloro-2-propenyl)-3-(2,3,4-trichlorophenyl)urea,

1-methyl-1-(1,2,2-trifluoroethyl)-3-(4-methoxyphenyl)urea,

1-ethyl-1-(1,2-dichloro-2,2-dibromoethyl)-3-(3-chloro-4-bromophenyl)urea,

1-methyl-1-(1,2,2-trichloromethyl)-3-(4-phenoxyphenyl)urea,

1-methyl-1-(1,2,2-trichloro-2-bromoethyl)-3-(4-[4'-chlorophenoxy]phenyl)urea,

1-ethyl-1-(1-chloro-2,2,2-tribromoethyl)-3-(4-phenylsulfoxyphenyl)urea,

1-methyl-1-(1,2,2-trichlorovinyl)-3-(4-phenylsulfonylphenyl)urea,

1-methyl-1-(1-methoxy-2,2,2-trichloroethyl)-3-(2-fluorophenyl)urea,

1-methyl-1-(1-ethoxy-2,2,2-tribromoethyl)-3-(2-chlorophenyl)urea,

1-methyl-1-(1-methylmercapto-2,2,2-trichloroethyl)-3-(2,4-dichlorophenyl)urea,

1-methyl-1-(1-chloromethylmercapto-2,2,2-trifluoroethyl)-3-(4-methoxyphenyl)urea,

1-methyl-1-(1-butoxy-2,2,2-tribromoethyl)-3-(4-isopropoxyphenyl)urea,

1-butyl-1-(1-[2'-bromoethoxy]-2,2-dichloropropyl)-3-(2-trifluoromethylphenyl)urea,

1-methyl-1-(1-phenoxy-2-bromo-2,2-dichloroethyl)-3-(3-chloro-4-bromophenyl)urea,

1-methyl-1-(1-[2-fluorophenoxy]-2-bromo-3,3-dichloro-2-propenyl)-3-(2,4-dichlorophenyl)urea,

1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(2,6-dimethyl-4-methylsulfonylphenyl)urea,

O,O-dimethyl1-(N-methyl-N-2-fluorophenylcarbamoylamino)-2,2,2-trichloroethylphosphonate,

O,O-diethyl1-(N-methyl-N-3-chlorophenylcarbamoylamino)-2,2,2-trifluoroethylphosphonate,

O,O-dibutyl1-(N-ethyl-N-2,4-dinitrophenylcarbamoylamino)-2-bromo-2,2-dichloroethylphosphonate,

O-methyl-O-ethyl1-(N-methyl-N-4-phenoxyphenylcarbamoylamino)-2,2,2-tribromethylphosphonate,

O,O-diethyl1-(N-methoxy-N-2,3,5,6-tetrachlorophenylcarbamoylamino)-2,2-dichlorovinylphosphonate,

O,O-diethyl1-(N-methyl-N-4-ethoxyphenylcarbamoylamino)-2,2-dichloroethylphosphonate,

O,O-diethyl1-(N-methyl-N-3-chloro-4-bromophenylcarbamoylamino)-2,2,3,3-tetrachloropropylphosphonate,

1-methyl-1-(1-acetoxy-2,2,2-trichloroethyl)-3-(2,4-dichlorophenyl)urea,

1-methyl-1-(1-propionyloxy-2,2,2-trifluoroethyl)-3-(3,4-dichlorophenyl)urea

1-methyl-1-(1-chloroacetoxy-2-bromo-2,2-dichloroethyl)-3-(3,5-dichlorophenyl)urea,

1-methyl-1-(1-dithioacetoxy-2,2,2-trichloroethyl)-3-(2-fluorophenyl)urea,

1-(N-methyl-N-2,4-dichlorophenylcarbamoylamino)-2,2,2-trichloroethyl-N',N'-dimethyldithiocarbamate,

1-methyl-1-(1-N-methylcarbamoyloxy-2,2,2-trichloroethyl)-3-(2-fluorophenyl)urea,

1-methyl-1-(1-isocyanato-2,2,2-trichloroethyl)-3-(2,4-difluorophenyl)urea,

1-methyl-1-(1-isothiocyanato-2-bromo-2,2-dichloroethyl)-3-(2-trifluoromethylphenyl)urea,

1-methyl-1-(1-isocyanato-2,2,2-trifluoroethyl)-3-phenyl urea,

1-methoxy-1-(1-isocyanato-2,2,3,3-tetrachloropropyl)-3-(3-chloro-4-bromophenyl)urea,

N-[1-(N'-2-fluorophenylcarbamoyl-N'-methylamino)-2,2,2-trichloroethyl]O,O-dimethylthiophosphoramide,

N-[1-(N'-2,4-methoxyphenylcarbamoyl-N'-methylamino)-2-bromo-2,2-dichloroethyl]O,O-diethylphosphoramide,

N-[1-(N'-phenylcarbamoyl-N'-ethylamino)-2,2-dichloro-3,3-difluoropropyl]O,O-dimethylthiophosphoramide,

N-[1-(N'-2-nitrophenylcarbamoyl-N'-methoxyamino)-2-bromo-2-chloropropyl]O,O-diethylphosphoramide,

1-methyl-1-(1-carbmethoxymethylthio-2,2,2-trichloroethyl)-3-(2-fluorophenyl)urea,

1-methyl-1-(1-carbethoxymethylthio-2-bromo-2,2-dichloroethyl)-3-(3-chlorophenyl)urea,

1-methyl-1-(1-carbmethoxymethylthio-2,2-dichloro-3,3,3-trifluoropropyl)-3-(2,4-dichlorophenyl)urea,

1-methoxy-1-(1-chlorocarbmethoxymethylthio-2,2,2-tribromoethyl)-3-(4-methylphenyl)urea,

O,O-dimethylS-[1-(N-3-chlorophenylcarbamoyl-N-methylamino)-2,2,2-trichloroethyl]dithiophosphate,

O,O-diethylS-[1-(N-2-fluorophenylcarbamoyl-N-methylamino)-2-bromo-2,2-dichloroethyl]thiophosphate,

O,O-dimethylO-[1-(N-3-chloro-4-bromophenylcarbamoyl-N-ethylamino)-2,2,3,3,3-pentachloropropyl]thiophosphate

O,O-diethylS-[1-(N-4-phenoxyphenylcarbamoyl-N-methylamino)-2,2,2-trifluoroethyl]dithiophosphate,

O,O-dimethylS-[1-(N-2-trifluoromethylphenylcarbamoyl-N-methoxyamino)-2,2-dichloro-3,3,3-trifluoropropyl]dithiophosphate,

1-methyl-1-(1-methylsulfonyl-2,2,2-trichloroethyl)-3-(2-fluorophenyl)urea,

1-ethyl-1-(1-ethylsulfonyl-2,3,3-trichloro-1-propenyl)-3-(2,4-dichlorophenyl)urea,

1-methyl-1-(1-methylsulfonyl-2,2,2-trichloroethyl)-3-(5-pyrimidyl)urea.

The compounds of the present invention wherein X is OH and R³ is##STR14## are prepared by reacting a urea with an aldehyde according tothe following equation: ##STR15## wherein R, R¹, R², Z, R⁴ and a are asdefined above.

The urea reactants are known compounds of the prior art. The aldehydemay be compounds such as chloral (trichloroacetaldehyde),pentachloropropinoylaldehyde, dichloroacetaldehyde,dichlorobromoacetaldehyde, etc. The reaction (IV) may be accomplished inthe presence of a solvent or neat. Generally, stoichiometric amounts ofthe urea and aldehyde will be used. A small amount of acid, preferablysulfuric acid or perchloric acid, may be used. The reaction temperaturewill be from 20° to 100° C. Generally the reaction proceeds very rapidlyand will be complete in a matter of a few minutes. Reaction time of from30 seconds to 10 hours are considered sufficient.

The alpha-hydroxy compound is converted to the alpha-chloro compound(i.e., wherein X is chlorine) by reacting the product of reaction (IV)either in purified form or in the reaction mixture of reaction (IV) withthionyl chloride according to the following equation: ##STR16## whereinR, R¹, R², Z, R⁴ and a are as defined above.

The reaction (V) can be accomplished by using from a molar amount ofthionyl chloride to an excess of as much as 20 mols based on the urea.The reaction temperature will be from 20° to 100° C. and reaction timewill be from 1 to 20 hours. If desired, reactions (IV) and (V) may becombined to prepare the product of reaction (V) by simply mixing theurea reactant of reaction (IV), the aldehyde reactant of reaction (IV)and the thionyl chloride of reaction (V). The product of reaction (V)can be recovered by slurrying in a solvent such as diethyl ether ormethylene chloride, collecting the product on a filter, then properlypurifying by recrystallizing from a 1:1 mixture of 1,2-dimethoxyethaneand methylene chloride or from a 1:1 acetone and methylene chloridemixture.

In order to obtain the compounds wherein X is fluorine, bromine oriodine, the product of reaction (V) can be reacted with ammoniumfluoride, ammonium bromide or ammonium iodide as shown in reaction (VI)below to obtain the final product: ##STR17## wherein R, R¹, R², R⁴, Zand a are as defined above.

The reaction (VI) may also be conducted with an alkali metal fluoride,bromide or iodide, e.g., potassium fluoride.

The above reaction (VI) can be accomplished readily be mixing thereactants preferably in a solvent such as 1,2-dimethoxyethane in anamount of from 2 to 50% for a time from 1 to 20 hours at a temperaturefrom 20° to 100° C. The solvent is then removed and the product slurriedin ether and collected. Generally the reactant in brackets will be inmolar excess, in an amount from 5 to 100% of the urea reactant ofreaction (VI).

The other products of the present invention can be prepared by reactingthe alpha-chloro compound of reaction (V) with a variety of compounds,as shown in reaction (VII) below: ##STR18## wherein R, R¹, R², R⁴, R⁵,R⁶, R⁷, R⁸, U¹, Z and a are as defined above.

The above reaction (VII) can be accomplished readily by mixing thereactants preferably in a solvent such as 1,2-dimethoxyethane in anamount from 2 to 50% for a time from about 0.25 to 20 hours at atemperature from about 20° to 100° C. The solvent is then removed andthe product slurried in ether and collected. Generally the reactant inbrackets will be in excess, in an amount of 5 to 100% of the ureareactant of reaction (VII).

In order to prepare the compounds wherein R³ is ##STR19## the product ofreaction (VII) above is dehydrohalogenated at very mild basicconditions. The product of reaction (VII) is heated in a very mild baseat a temperature from 0° to 30° C. for a period of time from 15 minutesto 2 hours to accomplish dehydrohalogenation. It is essential that thebasic conditions be very mild; otherwise decomposition of the product ofreaction (VII) will occur.

EXAMPLES

The present invention will be more fully understood by reference to thefollowing examples.

EXAMPLE 1 Preparation of1-methyl-1-(1-hydroxyl)-2,2,2-trichloroethyl)-3-phenyl urea

1-methyl-3-phenyl urea (7.5 g, 0.05 mol) was reacted with 7.5 g (0.05mol) of chloral without solvent. The mixture was shaken for a shortperiod of time. After, 3 drops of perchloric acid were added and themixture heated gently for a few minutes to give a homogenous viscousoil. Upon cooling, a glass formed. The chemical analysis showed: %Cl,calc. 35.8, found 35.8; %N, calc. 9.4, found 8.0.

EXAMPLE 2 Preparation of1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(2-fluorophenyl)urea

N-methyl-N'-o-fluorophenyl urea (16.8 g, 0.1 mol) was combined with 22.5g (0.15 mol) chloral and 18.0 g (0.15 mol) thionyl chloride. Afterseveral minutes, an exothermicity was noted and the reaction mixturebecame a homogenous yellow oil. After 5 minutes more, a precipitatebegan to form. After 11/2 hours, a 3:1 mixture of diethylether:petroleum ether was added and the product was collected on afilter and dried. The solid, which weighed 25 g, melted at 130°-141° C.and analyzed as follows: %Cl, calc. 35.7, found 37.3; %N, calc. 9.5,found 9.5.

EXAMPLE 3 Preparation of1-methyl-1-1,2,2,2-tetrachloroethyl)-3-(3,4-dichlorophenyl)urea

1-(3,4-dichlorophenyl)-3-methyl urea (15.2 g, 0.07 mol) was combinedwith 15.0 g (0.1 mol) of chloral and 5 drops of concentrated sulfuricacid. The mixture was heated for an hour to effect reaction, thenstripped under vacuum. To the crude1-(3,4-dichlorophenyl)-3-(1-hydroxy-2,2,2-trichloroethyl)-3-methyl ureawas added an excess of thionyl chloride and the mixture was heatedgradually to a maximum of 65° C. Diethyl ether was added to the crudeproduct, and the insoluble product was collected on a filter, washedtwice with diethyl ether and dried. The 15.3 g of product, which meltedat 132°-140° C., analyzed as follows: %Cl, calc. 55.2, found 46.0.

EXAMPLE 4 Preparation of1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(4-phenoxyphenyl)urea

p-Phenoxyaniline (11.7 g, 0.063 mol) was dissolved in 25 ml1,2-dimethoxyethane (Ansul E-121) and heated to 65° C. Methyl isocyanate(3.7 g, 0.65 mol) was added over a period of 10 minutes. Heating andstirring were continued for 1 hour. Then chloral (14.8 g, 0.1 mol) wasadded to the hot solution, followed immediately by the addition of 11.9g (0.1 mol) thionyl chloride. It was kept at 65° C. for 41/2 hours. Thesolution was cooled to 40°, and 25 ml of methylene chloride was added.The solution was refluxed for one more hour and then allowed to cool.The solid which formed upon cooling was filtered, washed with methylenechloride to give 5.0 g (20% yield) of a white powder, melting point165°-167° C. A second crop, melting point 160°-162° C., weighed 5.5 g(22%). Elemental analysis showed: %Cl, calc. 34.8, found 34.35; %N,calc. 6.9, found 6.8; %C, calc., 47.1, found 47.5; %H, calc. 3.46, found3.3.

EXAMPLE 5 Preparation of1-methyl-1-(1-methylthio-2,2,2-trichloroethyl)-3-(2-fluorophenyl)urea

1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(2-fluorophenyl)urea (16.7 g,0.05 mol) was dissolved by heating (30°-40° C.) in 100 ccdimethoxyethane, then methylmercaptan was bubbled into the hot solutionfor 20 minutes. An initial exothermicity occurred, then the temperaturedropped gradually to 30° C. Removal of the solvent yielded a solid,which after being slurried in ether was collected on a filter and dried.The crystalline solid, 7 g, melted at 127°-130° C. and analyzed asfollows: %S, calc. 9.3, found 8.0; %Cl, calc. 30.8, found 26.9.

EXAMPLE 6 Preparation of1-methyl-1-(1-acetoxy-2,2,2-trichloroethyl)-3-(3,4-dichlorophenyl)urea

1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(3,4-dichlorophenyl)urea (7.7 g,0.02 mol) was dissolved in 200 ml dimethoxyethane, followed by theaddition of 1.5 g of ammonium acetate. The mixture was stirred for 2hours, filtered, and stripped of solvent. The residual mush was added toether and the ether-insoluble material filtered off. Next, the ether wasremoved under vacuum. The residual oil was added to chloroform and someundissolved material was removed by filtration. The filtrate wasevaporated to give 5.5 g of an oily product. The infrared and NMRspectra were consistent with the assigned structure. The chlorineanalysis was: %Cl, calc. 43.5, found 41.7.

EXAMPLE 7 Preparation of1-methyl-1-(1-isothiocyanato-2,2,2-trichloroethyl)-3-(3,4-dichlorophenyl)urea

1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(3,4-dichlorophenyl)urea (7.7 g,0.02 mol) was dissolved in 200 ml dimethoxyethane, followed by additionof 1.5 g (0.02 mol) of ammonium thiocyanate. The mixture was stirred for2 hours, filtered and stripped of solvent. Ether was added to theresidue, which was again filtered to remove a small amount of solid. Theremaining solvent was then removed, leaving a dark oil which solidifiedupon standing. This material had a melting point of 142°-146° C. Theinfrared spectrum of the material showed a broad absorption band at 4.9micron (for the --N═C═S group). Elemental analysis showed: %Cl, calc.,43.6, found 36.7; %S, calc. 7.9, found 6.3.

Other compounds of the present invention were prepared using the methodsas described above. These compounds are listed in Table I.

UTILITY

The ureas of the present invention are, in general, herbicidal in bothpre- and post-emergent applications. For pre-mergent control ofundesirable vegetation, these ureas will be applied in herbicidalquantities to the environment, e.g., soil infested with seeds and/orseedlings of such vegetation. Such application will inhibit the growthof or kill the seeds, germinating seeds and seedlings. For post-emergentapplications, the ureas of the present invention will be applieddirectly to the foliage and other plant parts. Generally they areeffective against weed grasses as well as broad-leaved weeds. Some maybe selective with respect to type of application and/or type of weed.

Pre- and post-emergent herbicidal tests on representative ureas of thisinvention were made using the following methods:

Pre-Emergent Test

Acetone solutions of the test ureas were prepared by mixing 750 mg urea,220 mg of a nonionic surfactant and 25 ml of acetone. This solution wasadded to approximately 125 ml of water containing 156 mg of surfactant.

Seeds of the test vegetation were planted in a pot of soil and the ureasolution was sprayed uniformly onto the soil surface at a dose of 100 mgper cm². The pot was watered and placed in a greenhouse. The pot waswatered intermittently and was observed for seedling emergence, healthof emerging seedlings, etc., for a 3-week period. At the end of thisperiod, the herbicidal effectiveness of the urea was rated, based on thephysiological observations. A 0-to-100 scale was used, 0 representing nophytotoxicity, 100 representing complete kill.

Post-Emergent Test

The test ureas were formulated in the same manner as described above forthe pre-emergent test. The concentration of the urea in this formulationwas 5000 ppm. This formulation was uniformly sprayed on 2 similar potsof 24-day-old plants (approximately 15 to 25 plants per pot) at a doseof 100 mg per cm². After the plants had dried, they were placed in agreenhouse and then watered intermittently at their bases, as needed.The plants were observed periodically for phytotoxic effects andphysiological and morphological responses to the treatment. After 3weeks the herbicidal effectiveness of the urea was rated, based on theseobservations. A 0-to-100 scale was used, 0 representing nophytotoxicity, 100 representing complete kill.

The results of these tests appear in Table II.

The amount of urea administered will vary with the particular plant partor plant growth medium which is to be contacted, the general location ofapplication--i.e., sheltered areas such as greenhouses as compared toexposed areas such as fields--as well as the desired type of control.For pre-emergent control of most plants, dosages in the range of about0.5 to 20 lbs/acre will be used. Such administration will give aconcentration of about 2 to 80 ppm urea distributed throughout 0.1acre-foot. For post-emergent application, such as foliar sprayapplication, compositions containing about 0.5 to 8 lbs urea per 100gals spray will be used. Such application is equivalent to about 0.5 to20 lbs urea per acre.

The herbicidal compositions of this invention comprise an herbicidalamount of one or more of the above-described ureas intimately admixedwith a biologically inert carrier. The carried may be a liquid diluent,such as water or acetone, or a solid. The solid may be in the form ofdust powder or granules. These compositions will also usually containadjuvants such as a wetting or dispersing agent to facilitate theirpenetration into the plant growth medium or plant tissue and generallyenhance their effectiveness. These compositions may also contain otherpesticides, stabilizers, conditioners, fillers, and the like.

One of the compounds of the present invention, namely1-methyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-(3-chlorophenyl)urea, wascompared with the related compound of the prior art, namely1-(1-hydroxy-2,2,2-trichloroethyl)-3-(3-chlorophenyl)urea. Thecomparison was for herbicidal effectiveness, the testing procedure beingsubstantially the same as described above. The results are shown inTable III.

                                      TABLE I                                     __________________________________________________________________________                                         Elemental Analysis   Melting                                                  Halogen                                                                              N      S      Point,              Compound                             Calc.                                                                            Found                                                                             Calc.                                                                            Found                                                                             Calc.                                                                            Found                                                                             °C.          __________________________________________________________________________    1-methyl-1-(1-ethoxy-2,2,2-trichloroethyl-3-(2-fluoro-                                                          Cl 27.2                                                                             27.6                                  phenyl) urea                      F  7.3                                                                              7.2               162-163             1-methyl-1-(1-ethoxy-2,2,2-trichloroethyl)-3-(2-chloro-                       phenyl) urea                         38.4                                                                             38.8              124-127             1-methyl-1-(1-ethoxy-2,2,2-trichloroethyl)-3-(2-trifluoro-                                                      Cl 22.8                                                                             22.6                                  methylphenyl) urea                F  18.3                                                                             18.6              123-127             1-methyl-1-(1-methoxy-2,2,2-trichloroethyl-3-(3-tolyl),                                                            32.6                                                                             30.5                                                                              8.6                                                                              8.2        133-135             1-methyl-1-(1-ethoxy-2,2,2-trichloroethyl)-3-(3-chloro-                       phenyl) urea                         39.4                                                                             38.7                                                                              7.8                                                                              7.0        104-106             1-methyl-1-(1-methoxy-2,2,2-trichloroethyl)-3-(2-fluoro-                      phenyl) urea                         32.2                                                                             32.2                                                                              8.5                                                                              8.5        152-153             1-methyl-1-(1-methylthio-2,2,2-trichloroethyl)-3-(2-fluoro-                   phenyl) urea                         30.8                                                                             26.9       9.3                                                                              8.0 127-130             1-methyl-1-(1-ethylthio-2,2,2-trichloroethyl)-3-(2-fluoro-                    phenyl) urea                         29.5                                                                             29.1       8.9                                                                              8.4 144-147             1-methyl-1-(1-phenylthio-2,2,2-trichloroethyl)-3-(2-fluoro-                   phenyl) urea                         26.0                                                                             25.3       7.9                                                                              7.8 121-125             1-methyl-1-(1-methylthio-2,2,2-trichloroethyl)-3-(3-tolyl)                    urea                                 31.1                                                                             30.6       9.4                                                                              9.8 132-134             1-methyl-1-(1-methylthio-2,2,2-trichloroethyl)-3-(3-chloro-                   phenyl) urea                         39.2                                                                             38.5       8.8                                                                              9.1 127-130             1-methyl-1-(1-ethylthio-2,2,2-trichloroethyl)-3-(3-chloro-                    phenyl) urea                         37.8                                                                             35.4       8.5                                                                              8.0 142-145             1-methyl-1-(1-ethylthio-2,2,2-trichloroethyl)-3-(3,4-                         dichlorophenyl) urea                 43.2                                                                             40.1       7.8                                                                              7.3 125-128             1-methyl-1-(1-methylthio-2,2,2-trichloroethyl)-3-(3,4-                        dichlorophenyl) urea                 44.7                                                                             41.4       8.1                                                                              7.4 151-153             1-methyl-1-(1-ethylthio-2,2,2-trichloroethyl)-3-phenyl urea                                                        31.1                                                                             30.4       9.4                                                                              7.9 155-157             O,O--diethyl 1-(N--methyl-N--2-fluorophenylcarbamoylamino)-                   2,2,2-trichloroethyl phosphonate     24.5                                                                             22.5       7.1.sup.1                                                                        7.4.sup.1                                                                         ≈95         O,O--dimethyl 1-(N--methyl-N--3-chlorophenylcarbamoylamino)-                  2,2,2-trichloroethyl phosphonate     33.5                                                                             34.2       7.3.sup.1                                                                        7.0.sup.1                                                                         oil                 O,O--dimethyl 1-[N--(3,4-dichlorophenylcarbamoyl)-N--methyl-                  amino]-2,2,2-trichloroethyl phosphonate                                                                            38.6                                                                             39.0       6.8.sup.1                                                                        7.0.sup.1                                                                         oil                 O,O--diethyl 1-[N--(3-chlorophenylcarbamoyl)-N--methylamino]-                 2,2,2-trichloroethyl phosphonate     31.4                                                                             28.8       6.9.sup.1                                                                        6.7.sup.1                                                                         oil                 1-[N'--(2-fluorophenylcarbamoyl)-N'--methylamino]-2,2,2-                      trichloroethyl-N,N--dimethyldithio carbamate                                                                       25.4                                                                             24.0       15.3                                                                             13.9                                                                              142-145             1-methyl-1-(1-acetoxy-2,2,2-trichloroethyl)-3-(3-chloro-                      phenyl) urea                         38.0                                                                             34.6                                                                              7.5                                                                              7.0        150-152             1-methyl-1-(1-N--methylcarbamoyloxy-2,2,2-trichloroethyl)-                    3-(3-chlorophenyl) urea              36.5                                                                             30.2                                                                              10.7                                                                             9.2        oil                 1-methyl-1-(1-isothiocyanato-2,2,2-trichloroethyl)-3-(2-                      fluorophenyl) urea                   29.8                                                                             30.0       9.0                                                                              9.0 133-134             N--[1-(N'--3-chlorophenylcarbamoyl-N'--methylamino)-2,2,2-                    trichloroethyl] O,O--dimethylthiophosphoramide                                                                     31.2                                                                             25.2       7.1                                                                              6.7 oil                 N--[1-(N--{3,4-dichlorophenylcarbamoyl}-N--methylamino)-2,2,2-                trichloroethyl] O,O--dimethylthiophosphoramide                                                                     36.2                                                                             37.2       6.5                                                                              6.5 oil                 1-methyl-1-(1-carbethoxymethylthio-2,2,2-trichloroethyl)-                     3-(3-chlorophenyl) urea              32.7                                                                             31.7       7.4                                                                              7.0 oil                 1-methyl-1-(1-carbethoxymethylthio-2,2,2-trichloroethyl)-                     3-(3,4-dichlorophenyl) urea          37.8                                                                             34.9       6.8                                                                              6.9 oil                 1-methyl-1-(1-carbethoxymethylthio-2,2,2-trichloroethyl)-                     3-(2-fluorophenyl) urea              25.4                                                                             25.7       7.7                                                                              7.4 oil                 1-methyl-1-(1-carbethoxymethoxy-2,2,2-trichloroethyl)-3-                      (3-chlorophenyl) urea                34.0                                                                             30.3                                                                              6.7                                                                              6.5        oil                 1-methyl-1-(1-carbethoxymethoxy-2,2,2-trichloroethyl)-3-                      (3,4-dichlorophenyl) urea            39.2                                                                             36.7                                                                              6.2                                                                              5.4        oil                 1-methyl-1-(1-carbethoxymethoxy-2,2,2-trichloroethyl)-3-                                                        Cl 26.4                                                                             26.6                                  (2-fluorophenyl) urea             F  4.7                                                                              4.8               oil                 O,O--dimethyl S--(1-[N--3-chlorophenylcarbamoyl-N--methyl-                    amino]-2,2,2-trichloroethyl)dithiophosphate                                                                        30.1                                                                             26.4       13.6                                                                             12.7                                                                              148-151             O,O--diethyl S--[1-(N--3,4-dichlorophenylcarbamoyl-N--                        methylamino)-2,2,2-trichloroethyl]dithiophosphate                                                                  28.4                                                                             26.5       12.8                                                                             12.2                                                                              158-160             O,O--dimethyl S--[1-(N--3,4-dichlorophenylcarbamoyl-N--methyl-                amino)-2,2,2-trichloroethyl]dithiophosphate                                                                        35.0                                                                             32.4       12.6                                                                             11.6                                                                              181-183             O,O--dimethyl S--[1-(N--2-fluorophenylcarbamoyl-N--methylamino)-              2,2,2-trichloroethyl]dithiophosphate 23.3                                                                             23.5       14.1                                                                             14.0                                                                              115-117             O,O--diethyl S--[1-(N--3,4-dichlorophenylcarbamoyl-N--methyl-                 amino)-2,2,2-trichloroethyl]dithiophosphate                                                                        33.1                                                                             32.6       12.0                                                                             11.8                                                                              170-173             O,O--diethyl S--[N--2-fluorophenylcarbamoyl-N--methylamino)-                  2,2,2-trichloroethyl]dithiophosphate 21.9                                                                             22.1       13.2                                                                             13.9                                                                              150-153             1-methyl-1-(1-isothiocyanato-2,2,2-trichloroethyl)-3-                         cyclohexyl urea                             12.2                                                                             11.5       123-124             1-methyl-1-(1-isothiocyanato-2,2,2-trichloroethyl)-3-                         cyclopentyl urea                     32.2                                                                             31.8       9.7                                                                              9.6 105-106             1-methyl-1-(1-isothiocyanato-2,2,2-trichloroethyl)-3-t-butyl                  urea                                 33.4                                                                             33.5       10.1                                                                             10.0                                                                               98-101             1-methyl-1-(1-isothiocyanato-2,2,2-trichloroethyl)-3-                         dodecyl urea                         24.7                                                                             24.8       7.4                                                                              7.5   66-68.5           1-methyl-1-(1-methoxy-2,2,2-trichloro)-3-(3,4-dichlorophenyl)                 urea                                        7.4                                                                              8.0 34.7.sup.2                                                                       35.9.sup.2                                                                        165-168             1-methyl-1-(1-methylthio-2,2,2-trichloroethyl)-3-                             cyclohexyl urea                             8.4                                                                              8.1        148-150             1-methyl-1-(1-methylthio-2,2,2-trichloroethyl)-3-methyl                                                            40.1                                                                             38.6       12.1                                                                             11.1                                                                              167-168             1-methyl-1-(1-methylthio-2,2,2-trichloroethyl)-3-                             cyclopentyl urea                     33.3                                                                             33.4       10.0                                                                             10.2                                                                              121-123             1-methyl-1-(1-methylthio-2,2,2-trichloroethyl)-3-t-butyl                                                           34.6                                                                             35.1       10.4                                                                             10.4                                                                              102-103             1-methyl-1-(1-methylthio-2,2,2-trichloroethyl)-3-dodecyl                                                           25.3                                                                             23.3       7.6                                                                              7.2 48-49               1-methyl-1-(1-methylsulfonyl-2,2,2-trichloroethyl)-                           3-cyclohexyl urea                    29.1                                                                             27.3       8.8                                                                              8.6 146-149             1-methyl-1-(1-methylsulfonyl-2,2-dichlorovinyl)-3-methyl                                                           27.2                                                                             29.4       12.3                                                                             12.1                                                                              170-173             1-methyl-1-(1-methylsulfonyl-2,2,2-trichloroethyl)-3-                         cyclopentyl urea                     30.3                                                                             29.3       9.1                                                                              9.0 135-138             1-methyl-1-(1-methylsulfonyl-2,2-dichlorovinyl)-3-                            cyclopentyl urea                     22.5                                                                             22.5       10.2                                                                             10.0                                                                              147.5-149           1-methyl-1-(1-methylsulfonyl-2,2,2-trichloroethyl)-3-t-butyl                  urea                                 31.3                                                                             30.4       9.4                                                                              9.3 109-110             1-methyl-1-(1-N--methylcarbamoyloxy-2,2,2-trichloroethyl)-3-                  (3,4-dichlorophenyl) urea            42.0                                                                             44.5                                                                              9.9                                                                              7.8 34.1.sup.2                                                                       33.7.sup.2                                                                        oil                 1-methyl-1-(1-N--phenylcarbamoyloxy-2,2,2-trichloroethyl)-3-                  (3,4-dichlorophenyl) urea            36.6                                                                             36.2                                                                              8.7                                                                              6.5 42.1.sup.2                                                                       40.0.sup.2                                                                        oil                 1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(2-chlorophenyl)                                                           45.2                                                                             49.4              139-145             1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(4-chlorophenyl)                                                           45.2                                                                             41.9              175-180             1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(2,4-dichlorophenyl                   urea                                 45.5                                                                             43.6              190-193             1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(4-bromophenyl)                                                            12.7.sup.3                                                                       13.4.sup.3        187-190             1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(3-chlorophenyl)                                                           50.6                                                                             50.0                                                                              8.0                                                                              7.3        155-160             1-methyl-1-(1-chloro-2,2,2-tribromoethyl)-3-(3,4-dichloro-                    phenyl) urea                         11.6.sup.3                                                                       11.6.sup.3                                                                        5.4                                                                              5.5        155-158             1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-phenyl urea                                                                44.9                                                                             34.4                                                                              8.9                                                                              8.4        164-166             1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(3-chloro-4-bromo-                    phenyl) urea                         14.0.sup.3                                                                       13.7.sup.3                                                                        6.5                                                                              6.2        189-190             1-methyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-(3-chloro-                      phenyl) urea                         42.8                                                                             39.4                                                                              8.4                                                                              9.5        oil                 1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(2-trifluoro-                                                           Cl 30.6                                                                             30.9                                  methylphenyl) urea                F  16.4                                                                             16.2              145-148             1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(3,5-dichloro-                        phenyl urea                          55.4                                                                             50.3                                                                              7.3                                                                              7.5        150-157             1-methyl-1-(1,2,2-trichloro-2-bromoethyl)-3-(2-fluoro-                        phenyl) urea                         10.6.sup.3                                                                       10.5 .sup.3       139-142             1-methyl-1-(1-bromo-2,2,2-trichloroethyl)-3-(2-fluoro-                        phenyl) urea                      Br.sup.4                                                                         21.2                                                                             21.5              153-155             1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(4-methoxy-                           phenyl) urea                         41.1                                                                             40.1                                                                              8.1                                                                              8.2        176-179             1-methyl-1-(1,2,2-trichloro-2-bromoethyl)-3-(3,4-                             dichlorophenyl) urea                 14.0.sup.3                                                                       13.8.sup.3                                                                        6.2                                                                              6.3        166-169             1-methyl-1-(1,2,2-trichloro-2-bromoethyl)-3-(3-chloro-                        phenyl) urea                      Cl.sup.4                                                                         9.0                                                                              8.4               150-152             1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(3-trifluoro-                                                           Cl.sup.4                                                                         9.3                                                                              9.2                                   methylphenyl) urea                F  14.8                                                                             14.9              138-142             1-methyl-1-(1,2-dibromo-2,2-dichloroethyl)-3-(2-fluoro-                       phenyl) urea                      Br.sup.4                                                                         19.5                                                                             16.2                                                                              6.8                                                                              7.5        130-133             1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-[3-methyl-                            4-(4'-chlorophenylthio)phenyl] urea  37.5                                                                             35.4       6.8                                                                              6.8 152-154             1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-[3-methyl-4-(4'-                      chlorophenylsulfonyl)phenyl] urea    35.1                                                                             29.0       6.3                                                                              6.8 168-171             1-methyl-1-(1,2,2-trichloroethyl)-3-(3-chlorophenyl) urea                                                                 8.9                                                                              8.9 38.0.sup.2                                                                       38.0.sup.2                                                                        118-127             1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-[4-(4'-chloro-                        phenoxy)phenyl] urea                 40.1                                                                             39.6                                                                              6.3                                                                              6.3        153-156             1-methyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-(3-pyridyl)                                                          35.6                                                                             32.2                                                                              14.1                                                                             12.0       oil                 1-methyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-(2-thiazolyl)                   urea                                 34.9                                                                             35.8              oil                 1-methyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-(2-pyridyl)                                                          35.6                                                                             33.6              oil                 1-methyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-(2-pyrimidyl)                   urea                                 35.5                                                                             35.4                                                                              18.7                                                                             18.2       100-104             1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-cyclopentyl urea                                                                  9.1                                                                              8.7        132-136             1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-cyclohexyl urea                                                                   8.7                                                                              8.4          127-129.5         1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-methyl urea                                                                       11.0                                                                             10.9       73-76               1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-n-hexyl urea                                                                      8.7                                                                              9.2        45-55               1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-t-butyl urea                                                                      9.5                                                                              9.7 32.5.sup.2                                                                       31.7.sup.2                                                                        84-88               1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-n-dodecyl urea                                                             34.7                                                                             33.5                                                                              6.9                                                                              6.3        39-41               1-methoxy-1-(1,2,2,2-tetrachloroethyl)-3-(2-fluoro-                                                             Cl 40.6                                                                             40.2                                  phenyl) urea                      F  5.4                                                                              5.8               75-78               1-methyl-1-(1-fluoro-2,2,2-trichloroethyl)-3-(3,4-                                                              Cl 48.1                                                                             43.8                                  dichlorophenyl) urea              F  5.1                                                                              5.5               100-102             1-methyl-1-(1-fluoro-2,2,2-trichloroethyl)-3-phenyl                                                             Cl 35.5                                                                             35.5                                  urea                              F  6.3                                                                              5.7               152-153             1-methyl-1-(1-fluoro-2,2,2-trichloroethyl)-3-(3,5-                                                              Cl 32.5                                                                             32.3                                  dimethylphenyl urea               F  5.8                                                                              4.2               160-162             1-methyl-1-(1-fluoro-2,2,2-trichloroethyl)-3-                                                                   Cl 42.4                                                                             39.5                                  (3-chlorophenyl) urea             F  5.7                                                                              6.1               132-134             __________________________________________________________________________     .sup.1 phosphorus                                                             .sup.2 carbon analysis                                                        .sup.3 analysis for total halogen in milliequivalents per gram           

                                      TABLE II                                    __________________________________________________________________________                                     Herbicidal Effectiveness                                                      Pre/Post                                     Compound                         O    W    C    M    P    L                   __________________________________________________________________________    1-methyl-1-(1-ethoxy-2,2,2-trichloroethyl)-3-(2-                              fluorophenyl) urea               --   --   --   93/85                                                                              100/85                                                                             100/90              1-methyl-1-(1-ethoxy-2,2,2-trichloroethyl)-3-(2-tri-                          fluoromethylphenyl) urea         --   --   --   85/100                                                                             80/98                                                                              90/60               1-methyl-1-(1-methoxy-2,2,2-trichloroethyl)-3-(3-                             tolyl) urea                      --   80/--                                                                              --   --   --   100/--              1-methyl-1-(1-ethoxy-2,2,2-trichloroethyl)-3-(3-chloro-                       phenyl) urea                     --   --   --   --/100                                                                             75/95                                                                              75/100              1-methyl-1-(1-methoxy-2,2,2-trichloroethyl)-3-(2-                             fluorophenyl) urea               --   --   90/--                                                                              70/--                                                                              85/100                                                                             --/95               1-methyl-1-(1-methylthio-2,2,2-trichloroethyl)-3-(2-                          fluorophenyl) urea               100/100                                                                            100/100                                                                            100/95                                                                             100/100                                                                            100/100                                                                            100/100             1-methyl-1-(1-ethylthio-2,2,2-trichloroethyl)-3-(2-                           fluorophenyl) urea               100/--                                                                             100/--                                                                             100/--                                                                             100/95                                                                             100/--                                                                             100/90              1-methyl-1-(1-phenylthio-2,2,2-trichloroethyl)-3-(2-                          fluorophenyl) urea               100/--                                                                             --   85/--                                                                              100/95                                                                             100/--                                                                             85/75               1-methyl-1-(1-methylthio-2,2,2-trichloroethyl)-3-(3-                          tolyl) urea                      --   --   --   --   --   80/90               1-methyl-1-(1-methylthio-2,2,2-trichloroethyl)-3-(3-                          chlorophenyl) urea               --   --   --   --/70                                                                              --   --/70               1-methyl-1-(1-ethylthio-2,2,2-trichloroethyl)-3-(3-                           chlorophenyl) urea               --   --   --   --/70                                                                              --   --                  1-methyl-1-(1-ethylthio-2,2,2-trichloroethyl)-3-                              (3,4-dichlorophenyl) urea        --/100                                                                             94/100                                                                             --/90                                                                              --   --   --                  1-methyl-1-(1-methylthio-2,2,2-trichloroethyl)-3-                             (3,4-dichlorophenyl) urea        --   75/93                                                                              --   --   --   --                  1-methyl-1-(1-ethylthio-2,2,2-trichloroethyl)-3-                              phenyl urea                      --   --   --   75/--                                                                              --   --                  O,O--diethyl 1-(N--methyl-N--2-fluorophenylcarbamoyl-                         amino)-2,2,2-trichloroethyl phosphonate                                                                        95/--                                                                              --   90/--                                                                              95/70                                                                              95/--                                                                              95/--               O,O--dimethyl 1-(N--methyl-N--3-chlorophenylcarbamoyl-                        amino)-2,2,2-trichloroethyl phosphonate                                                                        --/100                                                                             100/100                                                                            100/100                                                                            100/93                                                                             100/100                                                                            100/--              O,O--dimethyl 1-[N--(3,4-dichlorophenylcarbamoyl)-N--                         methylamino]-2,2,2-trichloroethyl phosphonate                                                                  --/100                                                                             75/100                                                                             80/100                                                                             80/100                                                                             90/100                                                                             85/100              O,O--diethyl 1-[N--(3-chlorophenylcarbamoyl)-N--methyl-                       amino]-2,2,2-trichloroethyl phosphonate                                                                        70/100                                                                             95/100                                                                             100/100                                                                            75/100                                                                             90/100                                                                             80/100              1-methyl-1-(1-acetoxy-2,2,2-trichloroethyl)-3-                                (3,4-dichlorophenyl) urea        --   100/--                                                                             100/--                                                                             100/100                                                                            100/100                                                                            100/100             1-[N'--(2-fluorophenylcarbamoyl)-N'--methyl]amino-2,2,2-                      trichloroethyl-N,N--dimethyldithio carbamate                                                                   90/100                                                                             95/95                                                                              100/85                                                                             100/100                                                                            100/100                                                                            100/100             1-methyl-1-(1-acetoxy-2,2,2-trichloroethyl)-3-(3-                             chlorophenyl) urea               75/95                                                                              100/100                                                                            90/100                                                                             95/100                                                                             90/100                                                                             95/100              1-methyl-1-(1-N--methylcarbamoyloxy-2,2,2-trichloro-                          ethyl)-3-(3-chlorophenyl) urea   80/100                                                                             100/100                                                                            100/100                                                                            100/100                                                                            100/100                                                                            100/100             1-methyl-1-(1-isothiocyanato-2,2,2-trichloroethyl)-3-                         (3,4-dichlorophenyl) urea        --   --   95/--                                                                              100/100                                                                            95/90                                                                              95/100              1-methyl-1-(1-isothiocyanato-2,2,2-trichloroethyl)-3-                         (2-fluorophenyl) urea            85/75                                                                              --70 90/80                                                                              100/100                                                                            100/100                                                                            100/100             N--[1-N'--3-chlorophenylcarbamoyl-N'--methylamino)-2,2,2-                     trichloroethyl]O,O--dimethylthiophosphoramide                                                                  100/90                                                                             100/95                                                                             100/80                                                                             100/100                                                                            100/100                                                                            100/100             N--[1-(N--3,4-dichlorophenylcarbamoyl-N--methylamino)-2,2,2-                  trichloroethyl]O,O--dimethylthiophosphoramide                                                                  90/100                                                                             100/100                                                                            100/100                                                                            100/100                                                                            100/100                                                                            100/100             1-methyl-1-(1-carbethoxymethylthio-2,2,2-trichloro-                           ethyl)-3-(3-chlorophenyl) urea   75/--                                                                              85/95                                                                              100/--                                                                             100/100                                                                            100/70                                                                             95/95               1-methyl-1-(1-carbethoxymethylthio-2,2,2-trichloro-                           ethyl)-3-(3,4-dichlorophenyl) urea                                                                             99/100                                                                             94/100                                                                             99/100                                                                             --   --/100                                                                             --/80               1-methyl-1-(1-carbethoxymethylthio-2,2,2-trichloro-                           ethyl)-3-(2-fluorophenyl) urea   100/100                                                                            100/100                                                                            95/100                                                                             100/100                                                                            100/100                                                                            100/100             1-methyl-1-(1-carbethoxymethoxy-2,2,2-trichloroethyl)-                        3-(3-chlorophenyl) urea          90/100                                                                             100/100                                                                            100/100                                                                            100/100                                                                            100/100                                                                            100/100             1-methyl-1-(1-carbethoxymethoxy-2,2,2-trichloro-                              ethyl)-3-(3,4-dichlorophenyl) urea                                                                             --/75                                                                              90/100                                                                             100/95                                                                             100/100                                                                            100/100                                                                            100/100             1-methyl-1-(1-carbethoxymethoxy-2,2,2-trichloroethyl)-                        3-(2-fluorophenyl) urea          100/100                                                                            100/100                                                                            100/100                                                                            100/100                                                                            100/100                                                                            100/100             O,O--dimethyl S--[1-N--3-chlorophenylcarbamoyl-N--methyl-                     amino)-2,2,2-trichloroethyl]dithiophosphate                                                                    --   --   --   --/80                                                                              --   --/75               O,O--diethyl-S--[1-(N--3-chlorophenylcarbamoyl-N--methyl-                     amino)-2,2,2-trichloroethyl]dithiophosphate                                                                    70/--                                                                              85/--                                                                              --   --   --   --                  O,O--dimethyl S--[1-(N--3,4-dichlorophenylcarbamoyl-N--                       methylamino)-2,2,2-trichloroethyl]dithiophosphate                                                              --/73                                                                              --/90                                                                              --   --   --   --                  O,O--dimethyl S--[1-(N--2-fluorophenylcarbamoyl-N--                           methylamino)-2,2,2-trichloroethyl]dithiophosphate                                                              85/--                                                                              75/--                                                                              75/--                                                                              100/--                                                                             100/--                                                                             100/--              O,O--diethyl S--[1-(N--3,4-dichlorophenylcarbamoyl-N--                        methylamino)-2,2,2-trichloroethyl]dithiopohosphate                                                             --   --   --   --/70                                                                              --   --                  O,O--diethyl S--[1-(N--2-fluorophenylcarbamoyl-N--methyl-                     amino)-2,2,2-trichloroethyl]dithiophosphate                                                                    --   --   --   --   --/70                                                                              --                  1-methyl-1-(1-isothiocyanato-2,2,2-trichloroethyl)-3-                         cyclohexyl urea                  95/--                                                                              100/--                                                                             100/--                                                                             100/95                                                                             100/--                                                                             100/--              1-methyl-1-(1-isothiocyanato-2,2,2-trichloroethyl)-3-                         cyclopentyl urea                 --   90/--                                                                              90/--                                                                              100/--                                                                             100/--                                                                             100/80              1-methyl-1-(1-isothiocyanato-2,2,2-trichloroethyl)-                           3-t-butyl urea                   --   90/--                                                                              95/--                                                                              --/95                                                                              --/90                                                                              --/95               1-methyl-1-(1-methylsulfonyl-2,2,2-trichloroethyl)-3-                         cyclohexyl urea                  80/--                                                                              70/--                                                                              --   95/95                                                                              95/90                                                                              95/90               1-methyl-1-(1-methylsulfonyl-2,2-dichlorovinyl)-3-methyl                      urea                             --   --   --   --   --/70                                                                              --/95               1-methyl-1-(1-methylsulfonyl-2,2-dichlorovinyl-3-cyclo-                       pentyl urea                      --   --   --   --   75/--                                                                              85/--               1-methyl-1-(1-methylsulfonyl-2',2,2-trichloroethyl)-3-                        t-butyl urea                     --   80/--                                                                              --   --   --   75/--               1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(2-fluorophenyl)                      urea                             100/100                                                                            100/100                                                                            100/100                                                                            100/100                                                                            100/100                                                                            100/100             1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(3,4-                                 dichlorophenyl) urea             90/100                                                                             100/100                                                                            100/100                                                                            100/100                                                                            100/100                                                                            100/100             1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(2-chloro-                            phenyl) urea                     90/80                                                                              97/80                                                                              93/85                                                                              100/100                                                                            100/100                                                                            100/100             1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(4-chloro-                            phenyl) urea                     100/100                                                                            100/100                                                                            100/100                                                                            100/100                                                                            100/100                                                                            100/100             1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(2,4-                                 dichlorophenyl) urea             70/70                                                                              92/85                                                                              100/75                                                                             100/100                                                                            100/100                                                                            100/100             1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(4-bromo-                             phenyl) urea                     65/50                                                                              90/90                                                                              95/0 100/100                                                                            100/100                                                                            100/100             1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(3-chloro-                            phenyl) urea                     90/70                                                                              100/85                                                                             95/60                                                                              100/100                                                                            100/100                                                                            100/100             1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-phenyl urea                                                            100/100                                                                            100/100                                                                            100/85                                                                             100/100                                                                            100/100                                                                            100/100             1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(3-chloro-                            4-bromophenyl) urea              50/95                                                                              80/100                                                                             100/95                                                                             99/100                                                                             100/100                                                                            100/100             1-methyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-(3-                             chlorophenyl) urea               85/100                                                                             95/100                                                                             95/100                                                                             90/100                                                                             90/100                                                                             90/100              1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(2-trifluoro-                         methylphenyl) urea               --   96/--                                                                              91/--                                                                              --/85                                                                              --/90                                                                              --/85               1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(3,5-                                 dichlorophenyl) urea             --   --   --   100/80                                                                             100/--                                                                             100/70              1-methyl-1-(2-bromo-1,2,2-trichloroethyl)-3-(2-                               fluorophenyl urea                100/100                                                                            100/100                                                                            100/100                                                                            100/100                                                                            100/100                                                                            100/100             1-methyl-1-(1-bromo-1,2,2-trichloroethyl)-3-(2-                               fluorophenyl) urea               100/100                                                                            100/100                                                                            100/100                                                                            100/100                                                                            100/100                                                                            100/100             1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(4-                                   methoxyphenyl) urea              90/--                                                                              100/--                                                                             100/--                                                                             95/100                                                                             95/95                                                                              95/100              1-methyl-1-(2-bromo-1,2,2-trichloroethyl)-3-                                  (3,4-dichlorophenyl) urea        70/95                                                                              95/100                                                                             --/100                                                                             95/100                                                                             95/100                                                                             95/100              1-methyl-1-(2-bromo-1,2,2-trichloroethyl)-3-(3-chloro-                        phenyl) urea                     100/100                                                                            100/100                                                                            100/85                                                                             100/100                                                                            100/100                                                                            100/100             1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(3-tri-                               fluoromethylphenyl) urea         90/90                                                                              100/100                                                                            100/95                                                                             95/100                                                                             95/100                                                                             100/100             1-methyl-1-(1,2-dibromo-2,2-dichloroethyl)-3-                                 (2-fluoropohenyl) urea           --/100                                                                             --/100                                                                             --/100                                                                             --/100                                                                             --/100                                                                             --/100/                                                                       -1-methyl-1-(1,2                                                              ,2,2-tetrachloro                                                              ethyl)-3-[3-meth                                                              yl-                 4-(4'-chlorophenylthio)phenyl]urea                                                                             --   --   --   --/100                                                                             --/100                                                                             --/100              1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-[methyl-                              4-(4'-chlorophenylsulfonyl)phenyl]urea                                                                         --   --   --   --/100                                                                             --/90                                                                              --/95               1-methyl-1-(1,2,2-trichloroethyl)-3-(3-chlorophenyl) urea                                                      100/100                                                                            100/100                                                                            100/100                                                                            100/100                                                                            100/100                                                                            100/100             1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-(4-phenoxyphenyl)                     urea                             90/--                                                                              95/--                                                                              100/--                                                                             100/100                                                                            100/100                                                                            100/100             1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-[4-(4'-chloro-                        phenoxy)phenyl] urea             --   --   --   90/--                                                                              100/100                                                                            100/100             1-methyl-1-(1-hydroxy-2,2,2-trichloroethyl)-                                  3-(3-pyridyl urea                90/--                                                                              90/--                                                                              95/--                                                                              --   --   --/90               1-methyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-                                (2-thiazolyl) urea               85/--                                                                              90/--                                                                              85/--                                                                              95/100                                                                             100/90                                                                             100/100             1-methyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-                                2-pyridyl) urea                  --/95                                                                              80/95                                                                              --/90                                                                              --/100                                                                             70/100                                                                             90/100              1-methyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-                                (2-pyrimidyl) urea               70/--                                                                              90/--                                                                              90/--                                                                              --   --/70                                                                              --                  1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-cyclopentyl urea                                                       --   95/--                                                                              95/90                                                                              95/100                                                                             100/95                                                                             100/100             1-methyl-1-(1,2,2,2-tetrachloroethyl-3-cyclohexyl urea                                                         100/90                                                                             95/85                                                                              95/--                                                                              100/100                                                                            100/95                                                                             100/100             1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-methyl urea                                                            80/--                                                                              90/--                                                                              90/--                                                                              --   90/--                                                                              70/--               1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-n-hexyl urea                                                           --   --   --   --/100                                                                             --/95                                                                              --/95               1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-t-butyl urea                                                           90/--                                                                              90/--                                                                              90/--                                                                              70/--                                                                              --   --                  1-methyl-1-(1,2,2,2-tetrachloroethyl)-3-n-dodecyl urea                                                         80/--                                                                              90/--                                                                              90/--                                                                              --/70                                                                              95/80                                                                              100/80              *1-methyl-1-(1-fluoro-2,2,2-trichloroethyl)-3-                                (3,4-dichlorophenyl) urea        20/30                                                                              85/30                                                                              95/95                                                                              95/90                                                                              99/90                                                                              99/100              *1-methyl-1-(1-fluoro-2,2,2-trichloroethyl)-3-phenyl urea                                                      98/75                                                                              98/45                                                                              98/45                                                                              100/90                                                                             100/95                                                                             98/95               *1-methyl-1-(1-fluoro-2,2,2-trichloroethyl)-3-(3,5-                           dimethylphenyl) urea             85/0 98/0 98/0 100/10                                                                             100/10                                                                             100/0               *1-methyl-1-(1-fluoro-2,2,2-trichloroethyl)-3-                                (3-chlorophenyl) urea            90/0 99/95                                                                              100/75                                                                             100/100                                                                            100/100                                                                            100/100             __________________________________________________________________________     *tested at 33 micrograms/cm.sup.2                                        

                                      TABLE III                                   __________________________________________________________________________    (Comparison of compound of the present invention with prior art               compound)                                                                                                 O   W   C   M   P   L                             __________________________________________________________________________    1-methyl-1-(1-hydroxy-2,2,2-trichloroethyl)-3-                                (3-chlorophenyl) urea       85/100                                                                            95/100                                                                            95/100                                                                            90/100                                                                            90/100                                                                            90/100                        1-(1-hydroxy-2,2,2-trichloroethyl)-3-(3-chlorophenyl) urea                                                0/60                                                                              0/90                                                                              0/90                                                                              10/35                                                                             35/40                                                                             30/40                         __________________________________________________________________________     Tables II and III:                                                            O = Wild Oats (Avena fatua)                                                   W = Watergrass (Echinochloa crusgalli)                                        C = Crabgrass (Digitaria sanguinalis)                                         M = Mustard (Brassica arvensis)                                               P = Pigweed (Amaranthus retroflexus)                                          L = Lambsquarter (Chenopodium album)                                     

What is claimed is:
 1. A compound of the formula ##STR20## wherein R isan aliphatic hydrocarbyl group of 1 to 12 carbon atoms substituted with0 to 4 halogen atoms of atomic numbers 17 to 35, an alicyclichydrocarbyl group of 3 to 8 carbon atoms substituted with 0 to 4 halogenatoms of atomic numbers 17 to 35, an aryl group of 6 to 12 carbon atomssubstituted with 0 to 5 halogen atoms of atomic numbers 9 to 35, nitro,alkyl of 1 to 4 carbon atoms, alkoxy of 1 to 4 carbon atoms, alkylthioof 1 to 4 carbon atoms, or 0 to 1 alkylsulfoxy of 1 to 4 carbon atoms,alkylsulfonyl of 1 to 4 carbon atoms, trifluoromethyl, phenoxy,phenylthio, phenylsulfoxy, phenylsulfonyl, the phenoxy, phenylthio,phenylsulfoxy or phenylsulfonyl being substituted on the aromaticnucleus with 0 to 5 halogens of atomic numbers 9 to 35 or alkyl of 1 to4 carbon atoms; or a heterocyclic group selected from the groupconsisting the thiazolyl, pyridyl, pyrimidyl, oxazolyl, isothiazolyl,furyl, and thienyl and wherein said heterocyclic group is attached tothe urea nitrogen via a carbon atom; R¹ is hydrogen or alkyl or 1 to 4carbon atoms; R² is alkyl of 1 to 4 carbon atoms or alkoxy of 1 to 4carbon atoms; a is 0 to 1; R⁴ is hydrogen or CW₃ ' wherein W' ishydrogen or halogen of atomic numbers 9 to 35; Z is halogen of atomicnumbers 9 to 35; and R⁶ is alkyl of 1 to 4 carbon atoms.
 2. The compoundof claim 1 wherein R is 3-chlorophenyl; R¹ is hydrogen; R² is methyl; R⁶is methyl; Z is chloro; and a is
 0. 3. Compound of claim 1 wherein R isalkyl of 1 to 12 carbon atoms substituted with 0 to 4 halogen atoms ofatomic number 17 to 35 or a cycloalkyl group of 3 to 8 carbon atomssubstituted with 0 to 4 halogen atoms of atomic number 17 to
 35. 4.Compound of claim 1 wherein R is phenyl substituted with 0 to 5 halogenatoms of atomic number 9 to 35, nitro, alkyl of 1 to 4 carbon atoms,alkoxy of 1 to 4 carbon atoms, alkylthio of 1 to 4 carbon atoms or 0 to1 alkylsulfoxy of 1 to 4 carbon atoms, alkylsulfonyl of 1 to 4 carbonatoms, trifluoromethyl, phenoxy, phenylthio, phenylsulfoxy,phenylsulfonyl, the phenoxy, phenylthio, phenylsulfoxy or phenylsulfonylbeing substituted on the aromatic nucleus with 0 to 5 halogen atoms ofatomic number 9 to
 35. 5. Compound of claim 1 wherein R is phenyl orphenyl substituted with 1 to 2 halogens of atomic number 9 to 35, alkylof 1 to 2 carbon atoms, alkoxy of 1 to 2 carbon atoms or 1trifluoromethyl.
 6. Compound of claim 5 wherein a is 0 and Z is chlorineor bromine.
 7. Compound of claim 1 wherein R is phenyl substituted with1 to 2 fluorine, chlorine or bromine atoms, R¹ is hydrogen, R² ismethyl, a is
 0. 8. An herbicidal composition comprising an herbicidallyeffective amount of the compound of claim 1 and a biologically inertcarrier.
 9. A method for controlling the growth of undesirablevegetation which comprises applying an herbicidally effective amount ofthe compound of claim 1 to the vegetation or the growth medium of thevegetation.
 10. A method for controlling the growth of undesirablevegetation which comprises applying an herbicidally effective amount ofthe compound of claim 7 to the vegetation or the growth medium of thevegetation.